Unwind stand

ABSTRACT

The present disclosure relates to an unwind stand, having a cooperating slitter, which has particular utility with an apparatus for making box blanks or similar items from a continuous strip unwound from a roll of board stock. The cooperative effect of the unwind stand and the slitter, is that box making and other machines which can be fed with roll stock can be more economically utilized because any desired width of web can be drawn from a large mill roll which is less expensive than purchasing the same amount of material in small, made to order rolls. The web strip removed for use does not cause the remainder of the roll to be unwound.

w States Patent Eggert et a1.

Nov. 5, 1974 UNWIND STAND Inventors: Ralph H. Eggert, Watergate Condominium No. 224, Kings Hyw., Rt. 41, Maple Shade, N.l.; Quentin T. Woods, 952 Yarmouth, San Jose, Calif.

Filed: June 18, 1973 Appl. No.: 371,205

Related U.S. Application Data Division of Ser. No. 149,302, June 2, abandoned.

[52] U.S. Cl 82/92, 82/93, 82/100, 82/101 [51] Int. Cl B231) 5/14 [58] Field of Search 82/78, 46, 71, 47, 101, 82/92, 93, 100; 242/562, 56.6, 56.7; 83/469, 472, 102, 8

[5 6] References Cited UNITED STATES PATENTS 7/1895 Titsworth 82/461 X 5/1972 Voigt 82/101 FOREIGN PATENTS OR APPLICATIONS 880,121 9/1971 Canada 82/78 1,755 5/1874 Great Britain 509,241 7/1939 Great Britain 83/8 Primary ExaminerFrancis S. Husar Assistant ExaminerWilliam R. Briggs Attorney, Agent, or Firm-C. E. Tripp [57] ABSTRACT The present disclosure relates to an unwind stand, having a cooperating slitter, which has particular utility with an apparatus for making box blanks or similar items from a continuous strip unwound from a roll of board stock. The cooperative effect of the unwind stand and the slitter, is that box making and other machines which can be fed with rolll stock can be more economically utilized because any desired width of web can be drawn from a large mill roll which is less expensive than purchasing the same amount of material in small, made to order rolls. The web strip removed for use does not cause the remainder of the roll to be unwound.

4 Claims, 6 Drawing Figures PATENIEBnnv 51974 I Saw 1 W 5 3,845,678

l UNWIND STAND This is a divisional application of our application Ser. No. 149,302, filed on June 2, 1971, now abandoned in favor of continuation application Ser. No. 382,433 filed July 25, I973 and having the same assignee.

BACKGROUND OF THE INVENTION The basic structure of a rigid paperboard box dictates use of a plurality of distinct and essentially uncorrelated machinery. Briefly, the board material is supplied in the form of rectangular sheets, several hundred in number, defining a registered stack mounted on a skid. The skid is positioned in a convenient location adjacent a slitting and scoring machine where an operator removes a quantity from the stack and feeds them, one at a time, through the slitting and scoring machine. Scoring and slitting, depending upon the size of the box desired, reduce the parent sheet to two or more strips with each strip having two score lines parallel to each edge of the strip. After a sufficient number of strips have been slit and scored, each of the strips is then scored and slit transversely to produce a plurality of smaller rectangular blanks having perpendicularly related score lines whose distance from the blank edge is equal to the depth of the box part.

Another procedure followed in producing rigid box blanks is generally referred to as die-cutting. This method involves taking a standard size sheet of board, usually 26 inches by 38 inches, and placing it on the lower platen of a press. The upper platen of the press is provided with a die configuration that produces a series of cut and score lines which are arranged to produce one or a multiplicity of box parts. This method of necessity entails a significant amount of scrap since all of these box parts are located inwardly of the edges of the sheet. After the sheet is removed an operator must break out all the box parts and stack them for subsequent erection and staying. The die-cutting method in some instances makes use of roll stock wherein the strip of web is intermittently fed to the die press. This technique requires purchase ofa roll stock of a particular width equal to the major or minor dimension of the box blank.

SUMMARY OF THE INVENTION According to the preferred embodiment of the present invention, a continuous web for a box making or other machine is provided from a full parent roll of board material mounted on an unwind stand. The unwind stand includes a slitting device for progressively slitting a strip, from the parent roll, whose width is equal to one of the major dimensions ofthe desired box blank. Any desired width can be removed from the parent roll. Thus, the present invention provides practical means to use a full width mill roll, from which a web strip of predetermined width is continually generated as the mill roll is rotated, to be formed into box blanks, or other end products. It should be noted that only the required strip is unwound; the balance of the mill roll remains wound.

An important resulting benefit derived from using roll stock with means for progressively slitting a band therefrom of a desired width, is that an inventory of various sheet sizes is obviated, and in die cutting operations the usual waste of about a quarter of an inch around the periphery of each sheet, is avoided. Further,

purchase of sheet material is more costly as part of its price includes sheeting, stacking and banding for shipment by the mill. Roll stock is cheaper than sheets, and slitting a portion of the roll as it is being used also accurately establishes one of the dimensions for its ultimate use.

While the present invention discloses use of paperboard roll stock for making box blanks it has utility in a variety of situations where a band of web material is desirable. For example, the unwind and slitter mechanism of the present invention can be used in conjunc tion with core winding machines or processes where a web strip of desired width is not available from the mill, because the width of the web is too narrow, and in situations where one desires to slit a portion from roll stock without rewinding and slitting the entire roll.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective of a box blank making apparatus incorporating the unwind stand and slitter mechanism of the present invention.

FIG. 2 is a diagrammatic perspective illustrating the process of web slitting, scoring, cutting and corner removal for producing box blanks.

FIG. 3 illustrates the unwind stand apparatus in enlarged elevation.

FIG. 4 is a fragmentary enlarged plan of the apparatus shown at the left side of FIG. 1.

FIG. 5 is an enlarged section, taken substantially along the line 5-5 on FIG. 4, showing the web slitting knife and the means provided for regulating the depth of cut.

FIG. 6 is a section of FIG. 5 taken substantially along the line 6-6 on FIG. 5.

GENERAL ARRANGEMENT OF THE PREFERRED EMBODIMENT FIG. 1 shows a perspective of a box making apparatus incorporating the principles of the present invention in an unwind stand and slitter mechanism 10. The mechanism 10 comprises an unwind stand 12 including a movable base plate 14 mounted on guide rollers 16, some of which in turn roll on gib tracks 18 parallel to the axis of a parent roll R. The base plate 14 has secured thereto laterally spaced upwardly extending side frames 20. The side frames 20 rotatably support a core shaft 22 on which is mounted the parent roll R of web material suitable, in the present example, for making rigid box blanks. A disc brake 24 is mounted on the core shaft for arresting rotation of the core shaft 22. Adjacent the unwind stand 12, and in longitudinal alignment therewith, is a base plate 26 supporting a web slitting device, generally indicated by the numeral 30, comprising a rotary slitting knife 32 carried by arms 34 The lower end of the arms are slidably adjustably mounted on a laterally extending guide frame 36 which is pivotally mounted on transversely spaced upwardly extending frames 38 supported on the base plate 26.

Downstream of the web slitting device and also supported on the base plate 26 are upwardly extending side frames 40 between which web decurling rolls, generally indicated by the numeral 42, web drive rolls 44 and a web tension dancer frame 46 are mounted. A web strip WS, cut by the slitting knife 32, is directed over a large diameter idler roll 49 and under and over decurling rolls 50 and 52 (FIG: 3) which are associated with the remainder of the overall box blank forming apparatus as disclosed in the previously identified parent application. By means of a worm 54 keyed to a shaft which is rotated by a handwheel 56, a swinging block 60, and a similar block at the other ends of the decurling rolls 50 and 52, the degree to which the web strip is recurved or decurled depends upon the attitude assumed by the rolls 50 and 52 as selectively varied by turning the handwheel 56.

After the web strip traverses the decurling rolls it is received by the web drive rolls 44 which include a small diameter roll 62 and a roll 64 (FIG. 2) of larger diameter. The roll 64 is provided with a short shaft 66 having a sprocket 68 keyed thereon which is driven by a sprocket chain 70 trained about a drive sprocket 72. The drive sprocket 72 is mounted on the output shaft of a gear reducer 74 operatively connected to a SCR controlled DC'motor 80. The speed at which the web drive rolls 62 and 64 are rotated is dependent upon the tension of the web strip WS, as sensed by a web tension dancer frame, not shown, that is associated with low inertia reels 82 and 84 (FIG. 2) which are mounted to oscillate about an intermediate horizontal axis.

Variations in the tension of the web strip WS cause either clockwise or counterclockwise rotation of the reels 82 and 84 about said axis, whereby electrical controls, not shown, alter the input voltage, and hence the speed of the web drive motor 80. In operation, the web tension continually changes due to the intermittent motion of the web, thus resulting in continual oscillation of the reels 82 and 84 to keep the average web tension within predetermined limits.

Downstream of the reels 82 and 84, the box blank forming apparatus 53 includes shearing means 90 having pairs of web slitting rolls 92 and 94. The slitting wheels 94 are located to engage the web strip to remove a narrow waste portion WP only from the first web strip removed from the roll R, because this edge is inevitably damaged in the initial shipping and handling of the roll. Slitting wheels 92 are only required (after being laterally adjusted) when the last web strip is removed, in order to trim the opposite edge which was damaged before the roll was mounted in the unwind stand 12.

Following the shearing means 90 are scoring means 9.6, which employs scoring wheels 98 and 100 to produce longitudinal score lines LS. and intermittently driven draw rolls 102 that feed the scored and trimmed web to a rule die 104. The rule die transversely severs the web along a line T, and forms transverse score lines TS. At the same time, the rule die cuts through the web to produce waste corner pieces C which are intersected by the transverse cut line T and bounded by the longitudinal score lines LS and the edges of the web.

After the web strip WS has been provided with longitudinal and lateral score lines and issubstantially fully cut to form a series of interconnected box blanks B, it is moved by discharge rolls 106 to a corner knockout mechanism 108 which separates the box blanks B as a consequence of removing the corner portions C from the web strip.

FIG. 3 shows a portion of the unwinding and slitting machine in enlarged side elevation. The web slitting device 30 which carries the web slitting knife 32 is mounted for transverse movement between the laterally spaeed and aligned frames 38 which are supported on the base plate 26. Referring to F 1G. 4, which shows the web slitting device 30 in plan, it will be observed that the arm 34 comprises three generally L-shaped plates 34a, 34b and 340 having fixed to the upper end a tubular hub or spindle 110 within which is rotatably mounted a shaft 112 (FIG. 5) carrying the web slitting knife 32. A depth gauge roller 114 (FIG. 3) rotates by making contact with the surface of the web to be removed from the board stock supply roll R and is adjustable to control the depth of cut of the slitting knife 32. The roller 114 (FIG. 6) is rotatably mounted by means ofa roller bearing 118 fixed on a hub 120. The hub 120 is adjustable, by means ofa knob adjusted shaft 122 to set the depth of cut of the knife 32. The adjustment is maintained by a locking shaft 124. To adjust the surface of the depth gauge roller 114 relative to the cutting edge of the knife 32, a collar 126, having diametrically opposed flats 128, is clamped to the spindle 110. The hub 120 is also provided with diametrically opposed flat surfaces dimensioned to be slidably fitted on the flats 128. Strips 132 secured to the hub 120 retain the hub 120 and the collar 126 is assembled relation.

The tubular spindle 110 is designed so that the web slitting knife 32, the depth roller gauge 114 and the hub 120 can be mounted on the opposite end of the tubular spindle. This is accomplished by making both ends of the spindle 110 identical. As shown in FIG. 6, the spindle 110 counterbored for reception of a bearing 134 which is retained therein by a ring 136 secured by screws 138. The shaft 112 is formed with reduced diameter portion 140 being bored and threaded for reception of a stud 142. The stud is an integral part of a disc 144 received in a recess 146 formed in the knife 32. The disc 144 is secured to the knife by screws 148. Once the disc is attached to the knife 32, the stud is threaded into the thread bore of the shaft portion 140. An end cap 150 is centrally bored so that the shaft portion 140 projects therethrough. The cap 150 protects the bearing 134 from the web dust produced during the cutting operation.

The other end of the spindle 110 is made in an identical manner to mount the knife 32 on the opposite end of the spindle. The two-way mounting is provided for those instances where the web strip to be slit may be too narrow to provide a sufficient area of contact for the depth roller and therefore mounting the depth adjustment and the slitting wheel on the other end of the tubular spindle 110 will allow the depth roller gauge 114 to ride along or on a large area of the roll.

The arms 34 (FIG. 3) are interconnected and secured to tubular sleeves 156a and 156!) slidably mounted on transverse rods 158 and 160 having their ends fixed in links 162 and 164. Each of the links 162 and 164 are rotatably mounted, by means of a short stub shaft extension 166 and 168 held in bearings 170 supported by the frames 38. A threaded rod or lead screw 172, held against axial movement by a collar 174 and a hand wheel 176, extends through the side frames 38 and through the links 162 and 164. Rod 172 is threadedly received in a bushing 178 rigidly attached to the arm 340.

While the nominal adjustment made for removing a web strip WS of desired width is made by laterally moving the unwind stand 12 transversely relative to the direction of movement of the web strip WS, minor adjustments can be made by turning the hand wheel 176 to rotate the screw 172 and transversely move the web slitting device 30. A locking device comprising a screw fixed to a handle 182 serves to lock the web slitting device 30 against transverse movement by turning the handle to engage the end of the screw 180 with the shaft 150.

The web slitting device 30 is provided with the ability to controllably rotate about the axis of the lead screw 172. In order to produce a continuous web strip of a desired width, the slitting knife 32 must travel in a plane normal to the axis of the web roll R. Aside from the alignment of the unwind stand 12, the arms 34 must provide a degree of rigidity which will constrain the slitting knife 32 to travel in a predetermined path. One of the factors significantly contributing to this result is to insure that the cutting force the knife 32 imposes on the web is substantially constant as the knife pivots or moves in an arc from the outer wrap of the web roll toward the core. For this purpose, and in accordance with a feature of the present invention, a power cylinder 190 (FIG. 3) is provided. The link 162 is formed with an extension 162a having connected thereto a clevis 192 suitably secured to the end of the piston rod 194. Conduits 196 and 198, respectively, connected to the rod end and the head end of the piston 190, are connected to suitable controls supplying pressurized fluid simultaneously to the conduits 196 and 198 such that the net force or turning moment imparted to the link 162, and accordingly to the slitting wheel 32, is regulated to a predetermined amount. The lower end of the piston 190 is pivotally connected at 200 to a bracket 202 secured to the base plate 26.

Means are provided on the web slitting mechanism for initiating and terminating pivotal movement of the arms 34 about the axis defined by the lead screw 172. Such means preferably comprise limit switches LS6 and LS7 mounted on the frame 38 (at the bottom of FIG. 4) actuated by lobes 204 and 206 (FIG. 3) secured to the link 164. The lobe 204 is in contact with the arm of the switch LS6 to condition a control circuit (not shown) to interrupt pressure fluid to the cylinder 190. It should be noted that the slitting knife is at this time out of contact with the web roll R. Switch LS7 is contacted by the lobe 206 to control the limit of counterclockwise movement of the web slitting device 30, and this limit is set to prevent cutting of the core supporting the web roll. When the limit switch LS7 is actuated, the control circuit is conditioned to exhaust fluid from the head end of the cylinder 190 and admit pressure fluid through the conduit 196. The limit of counterclockwise rotation of the web slitting device 30 is shown in phantom line where the limit switch LS7 is actuated by the lobe 206 to terminate such movement and condition the control circuit to retract the piston rod 194 of the cylinder 190.

In view of the above detailed description of the preferred embodiment, it is apparent that by using roll stock and a slitting device operable to progressively produce a web strip of desired width, the percentage of usable web material is substantially increased as the only waste occurs at either end of the roll which is usually damaged by handling and storage. As opposed to the usual slitting machinery, which requires slitting and rewinding of an entire roll, the present invention gives the option of removing any portion of the web roll desired without unwinding the remaining portion of the web roll. Thus, the present invention eliminates the problem and expense of having rolled stock prepared outside the plant, and at the same time provides substantial economies in initial cost, shipping, handling and storage. Further, there is no possibility of edge damage to the stock. This eliminates a former problem where precut rolls are stored and used in conventional web handling systems, because repeated handling is likely to cause roll damage. It is considered that the present invention has utility not limited to rigid box roll stock, and is broadly useful in any roll-fed machine which uses a material available in mill roll size, or any other size which is a multiple of the required width, plus a trim allowance.

Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention.

1. Apparatus for severing a selected portion of a full mill roll from the remainder of the roll, said apparatus being ofthe type comprising an unwind stand for rotatably supporting the roll, an arm pivoted on said unwind stand and having a tubular hub, a shaft rotatable in said hub, a disc like cutter wheel mounted on one end of said shaft for severing said selected roll portion, and a depth gauge roller mounted on said hub on an axis of rotation that is parallel to that of said cutter wheel; the improvement wherein means are provided for adjustably shifting said depth gauge roller relative to said cutter wheel in a direction that is substantially normal to the mill roll surface while maintaining the axis of rotation of said depth gauge roller parallel to the axis of said cutter wheel, said adjusting means comprising a hub for said depth gauge roller that surrounds and clears said cutter shaft hub, shifting means acting between said cutter shaft hub and said depth gauge roller hub, and means for securing said depth gauge roller in its adjusted position.

2. The apparatus of claim 1, comprising collar means on said cutter shaft hub, said collar means having flats that are substantially normal to the mill roll surface and mating flats on said depth gauge roller hub.

3. The apparatus of claim 2, wherein said shifting means comprises a screw rotatably mounted in said collar means and threaded in said depth gauge roller hub.

gagement with the mill roll.

=l =l l l UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,845,678

DATED 1 November 5, 1974 INVENTOMS) I RALPH H. EGGERT and QUENTIN T. WOODS It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 21; change "is' to in-.

Note: On first page of Letters Patent the Assignee was omitted. Should be -Assignee FMC CORPORATION,

San Jose, Calif.-.

Signed and Scaled this twen ty-eight D 3) Of October 1 9 75 [SEAL] A ttest:

RUTH C. MASON C. MARSHALL DANN Arie-Sling Offl'te (ommissinner nj'larents and Trademarks 

1. Apparatus for severing a selected portion of a full mill roll from the remainder of the roll, said apparatus being of the type comprising an unwind stand for rotatably supporting the roll, an arm pivoted on said unwind stand and having a tubular hub, a shaft rotatable in said hub, a disc like cutter wheel mounted on one end of said shaft for severing said selected roll portion, and a depth gauge roller mounted on said hub on an axis of rotation that is parallel to that of said cutter wheel; the improvement wherein means are provided for adjustably shifting said depth gauge roller relative to said cutter wheel in a direction that is substantially normal to the mill roll surface whIle maintaining the axis of rotation of said depth gauge roller parallel to the axis of said cutter wheel, said adjusting means comprising a hub for said depth gauge roller that surrounds and clears said cutter shaft hub, shifting means acting between said cutter shaft hub and said depth gauge roller hub, and means for securing said depth gauge roller in its adjusted position.
 2. The apparatus of claim 1, comprising collar means on said cutter shaft hub, said collar means having flats that are substantially normal to the mill roll surface and mating flats on said depth gauge roller hub.
 3. The apparatus of claim 2, wherein said shifting means comprises a screw rotatably mounted in said collar means and threaded in said depth gauge roller hub.
 4. The apparatus of claim 1, wherein said cutter wheel is an idler wheel that is rotated solely by its engagement with the mill roll. 